Auxiliary thrust means for jetpropelled aircraft



Sept. 16, 1952 R, [MBERT r 2,610,465

AUXILIARY THRUST MEANS FOR JET-PROPELLED AIRCRAFT Filed Au 6, 1946 2 SHEETS-SHEET 1 Sept. 16, 1952 R. J. IMBERT ET AL 2, 65

AUXILIARY THRUST MEANS FOR JET-PROPELLED AIRCRAFT Filed Aug. 65,- 1946 2 SHEETSSHEET 2 m V P 5 4 in Z l a 0 35 m n I 0 Patented Sept. 16, 19 52 UNITED s'rAT s PATENT oFFlcs AUXILIARY 'rmws'r MEANS FOR JET- PROPELLED AIRCRAFT I Rogcr Jean Imbert France, assignors, ments, to Societe and Ren Anxionnaz, Paris, by direct and mesne assign- Rateau (Societe Anonyme),

Paris, France, a company of France Application August 6, 1946, Serial No. 688,594

" In France September 2'7, 1945 jet devices wherein the value of the propelling force or thrust produced predominates at least momentaneously all other considerations including efliciency and consumption of fuel. It is also well known that the thrust obtained depends chiefly on the maximum allowable-temperature for the motive cycle.

On the other hand, in some embodiments'of turbo-jet devices having a cooling air flow, only a .fraction of the operating air passes through the gas turbine and it is not possible to heat to a maximum both gaseous flows except downstream of the gas turbines but before the final expansion inside the reaction jet nozzle. This manner of operating allows, itis true, obtaining a maximum thrust anda'high efficiency but at theexpense of providing an intricate mechanical arrangement and generally speaking of dealing with an increased weight and cost price .of' the propeller. V

When the case is that of a short operation at maximum speed as for instance for intercepting airplanes or else of missiles, it is of .considerable interest to obtain a maximum thrust withoutithe drawbacks relating to weight and cost price as disclosed hereinabove.

Our invention satisfies this condition and has for object chiefly in constantly or temporarily superposing over the cycle of a turbo-jet one or I 2 Claims. (o1. 6035.6)

more supplementary cycles including either a mechanical compression of the operating air or else a compression through the recovery of the kinetic energy of the relative wind in a ram-jet or propulsive duct.

The following description and accompanying drawings corresponding thereto and given out by way of examples and by no means in a limitative sense will allow to understand how our invention may be embodied.

Figs. 1 and 2 illustrate diagrammatically a turbo-jet device with a supplementary cycle including a mechanical compression.

Fig. 3 illustrates a turbo-jet device with two ferent temperatures.

supplementary cycles of which one includes a mechanical compresssion and the other a compression through the recovery of the kinetic energy of the relative wind in a ram-jet;

Figs. 4 and 5 illustrate the same arrangement as .in the preceding figure (Fig. 3) with means for doing away with or reinserting into work the ram-jet. a

,According to our invention, it ispossiblelto asscociate with a turbo-jet device a first supplementary device operating in accordance with: a cycle including a mechanical compression.-

Fig. 1 illustrates diagrammatically in longitudinal cross-section this arrangement as awhole. .The turbo-jet comprises two streams of air the compression of which is ensured through a common compressor a of any type, butthe two streams separate after compression while feeding each a separate combustion chamber. @Only, one flow passes through the gas-turbine- In Fig. 1, 'a

illustrates the compressor wheel, b the annular,

space inside which is heated the flow which feeds the gas turbine d and thereaction jet nozzle e beyond said turbine, while 0 designates the annularspace inside whichis heated the second flow which is only a propelling flow, said space 0 ending with an annular reaction jet snozzle e.:

In this embodiment, the second :fiow. may be heated to a considerable temperaturefias'it does not act on any movablemember, the temperature of the first flow feeding the turbine being limited by the possibilities of'the latter as concerns itsmechanical behaviour.

The modification illustrated in also eludes two flows of air intended for combustion,

said flows receiving however separately their own vided as precedingly with its own combustion chamber b or 0 according to the flow considered.

Lastly, in the modification illustrated in Fig. 3, the arrangement includes the adjunction to the arrangement of Fig. 2 of a cycle providing for compression through the recovery of the kinetic energy of the relative wind, i. e., the adjunction of a ram-jet device, which is arranged outside the two preceding cycles. There are then three heating chambers b, c, 0' corresponding each to one flow and adapted to operate moreover at dif- These three chambers lead into three reaction jet nozzles, coaxial with one another and shown at e, e, e". The inlet pipe for the air into the ram-jet is divergent for the speeds for which the relative wind assumes a subsonic velocity and it is convergent-divergent for supersonic velocity.

It is obviously possible to contemplate diiierent combinations; in the case of Fig. 3, the two internal cycles are those of Fig. 2, but they may as well be those of Fig. 1.

It is of interest in the case of slow speeds oi v progression to render the outer cycles of the ram-jet device inoperative. accordance with a further embodiment of our invention, the outer casing maybe made, of twoparts sliding over one another. through their cooperating cylindrical portions. Figs. 4:- and 5 show such an arrangement wherein the two halves jf of the outer casing which have respectively a divergent and a convergent inner shape are mounted in relative sliding relationship so as to allow as desired a closing of the front air intake of the ram-jet at g as well as theclosing of. the nozzle c attherear of .the ramjetas shown in Fig. 4 or else. for opening. both.

said air intake. 9 and nozzle e as shown in Fig; 5,.

Of courselthe two halves. .].',.of. the outer casing mayassume any intermediatepositionu The sliding movementof the parts f, 1" may be controlled by'pistonsv Z, Z movable ina cylinder m. and operated, in a direction of movement,-by..

springs 11" and in the other directiomybyla liquid under pressure. issued. from: pipe; 0. and admitted by a. valve b. Obviously, all the known arrangement. for adjusting the cross-.sectionsiof the air intakes orthrough thenozzles mayxbe, applied to. the difierent kinds ofreactiomjet. propellers designed in. accordance. with .our in-v vention.

What we claim is: I v 1 1'. In an aircraft having for the pc-pulsion in normal flight. a mainjet;deviceof thekind comprising an air compressor. and-a, powerengine,

for driving the same, both. arranged in a casing extending. in afore-and-aft direction and provided with. a frontaperturefor the intake of. the atmosphericair andwith a jet nozzle. rearwardly directed, therprovisionl of. an auxiliary ram-jet engineihaving an. annular duct coaxially. arranged around the casing. of the main jet device, a front annular airintakecoaxial with said aperture of said main jet devicaarear annular exhaust noz To this end, and in means being further combined with said annular intake for throttling at will said intake.

2. In an aircraft having for the propulsion in normal flight a main jet device of the kind comprising an air compressor and a power engine for driving the same, both arranged in a casing extending in a fore-and-aft direction and provided with a front divergent aperture for the intake of thejatmospheric air and with a'jet nozzle rearwardly directed, the provision of an auxiliary ram-jet engine having an annular duct coaxiall-y arranged around the casing of the main jet device, a front annular air intake co-axial with said aperture of said main jet device, a rear annular exhaust nozzle coaxial with the jet nozzle ofv the main jet device, means to inject fuel into said annular duct, and means for igniting the fuel, said duct with its intake and its exhaust nozzle forming a ram-jet air-and-gas-cir cuit distinct from the circuit of said main jet device, said annular intake being divergentso as to perform the; total compression of the incorn-- ing air only by rain effect, said annular intake. forming a part mechanically separate from they remainder of said duct and being mounted so as to slide along the common axis of the main jet deviceand of said duct for throttling at will, 0W- ing to its divergent inner shape, the annular passage between them and the casing of the main jet "device.

ROGER JEAN IMBERT. RENE ANIQIONNAZ.

REFERENCES CITED The following references are of record in the Number Name Date 2,379,541 Planiol July 3, 1945 2,396,911. I Anx'ionnaz et al. Mar. 19, 1946 2,409,177 Allen et al. Oct. 15, 1946 2,464,724 Sdille Mar. 15, 1949 2,503,006, Stalker Apr. 4,1950 2,509,890 Stalker May 30, 1950 FOREIGN PATENTS Number I Country. Date 538,022 Great Britain July 17, 1941 522,163: France Mar. '22, 1921 50,033 France Aug. 1, 1939' (3rd Addition to No. 779,655)

v OTHER, REFERENCES r Ser. No. 367,666, Anxionnaz. etal. (A. P. 0.),

published. May. 25, 1943.

(Corresponds to Anxiounaz et a1. 2,396,911.) 

